JPH0687075A - Inclination control welding method - Google Patents

Abstract

PURPOSE:To provide the inclination control welding method to carry out control in an on-line system so that the welding attitude of a torch for a work and welding conditions can be kept optimally. CONSTITUTION:The distance for the work 2 of the torch 1 is measured momently by distance measuring sensors 15, 16 and 17 provided on the right and left sides and the front of the torch 1, relative right and left angles and front and rear angles for the work 2 of the torch 1 are controlled so that these are held at the specified angles, respectively based on the measured value, right and left absolute angles and front and rear absolute angles of the torch 1 are measured momently by a torch inclination measuring sensor 18 provided on the top of the torch 1 and the optimum welding conditions in accordance with the absolute angles of the torch 1 are selected out of the welding conditions by the absolute angles of the torch 1 based on the measured value to carry out control.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a tilt control welding method.

[0002]

2. Description of the Related Art Generally, the welding result is often influenced by the attitude of the torch with respect to the work, and particularly when welding a thin plate or the like, the effect of the attitude of the torch becomes large. The torch posture is maintained so that the torch angle is a right angle.

Further, even if the relative posture of the torch with respect to the work is well maintained, if the absolute angle of the torch and the work with respect to the horizontal / vertical is changed, the optimum welding conditions such as welding current will naturally occur. Since the arc voltage, welding speed, etc. will also change, it is necessary to change these welding conditions according to the absolute angle of the torch and the work.

Therefore, conventionally, when welding a work having a three-dimensional shape, the torch is mechanically moved so that the torch always moves while maintaining a posture perpendicular to the welded portion of the work. The optimum welding condition determined by the absolute angle of the torch at each position of the orbit where the torch is moved by the device is determined in advance by preliminary experiments and the like. The welding conditions were controlled programmatically according to the movement.

[0005]

However, in the above-mentioned conventional means, only the mechanically determined operation of the torch and the program control of the determined welding conditions are performed, and the changing work side. Since the torch welding posture and welding conditions were not controlled online in accordance with the shape of the torch, if the positioning of the torch side at the start of welding and the timing of changing the welding conditions are incorrect, There was a problem that welding results could not be obtained, and it was not versatile for works of different shapes.

The present invention has been made in view of the above circumstances, and an object of the present invention is to provide a tilt control welding method in which online control is performed so that the welding posture and welding conditions of a torch with respect to a work can be optimally maintained. .

[0007]

According to the present invention, the distance measuring sensors provided at least at three positions of the torch measure the distance of the torch from the work moment by moment, and the distance of the torch relative to the work is measured based on the measured value. While controlling the left and right angles and the frontward receding angle so that each can be maintained at a predetermined angle, the torch tilt measurement sensor provided at the required position of the torch measures the absolute angle of the left and right of the torch and the absolute angle of the front and back moment by moment. The present invention relates to a tilt control welding method characterized by selecting optimum welding conditions according to the absolute angle of a torch based on the measured values.

[0008]

Therefore, according to the present invention, the right and left angles relative to the work and the frontward receding angle can be grasped momentarily based on the distances measured by the distance measuring sensors. The torch welding posture is controlled so that the left and right angles and the frontward receding angle relative to the work of the torch are maintained at the predetermined optimum angles, respectively. It is possible to control the welding posture online.

Further, based on the absolute angles of the left and right sides of the torch and the absolute angles of the front and back sides measured by the torch tilt measuring sensor, the torch is selected from welding conditions for each absolute angle of the torch previously obtained by preliminary experiments and the like. By selecting the optimum welding conditions according to the absolute angle of, the optimum torch welding conditions can be controlled online.

[0010]

Embodiments of the present invention will be described below with reference to the drawings.

1 to 7 show an example of an apparatus for carrying out the method of the present invention.

In the drawing, 1 denotes a torch, 2 denotes a work, and the torch 1 is moved by the torch holding device 3 shown in FIGS. 4 to 6 in the left-right direction (direction perpendicular to the welding proceeding direction) and the front-back direction (welding proceeding direction). The torch holding device 3 itself is supported by a welding carriage 25 (see FIG. 5) that travels in the welding advancing direction.

The torch holding device 3 includes the welding carriage 2
5, a front and rear guide rail 5 which is attached via a support arm 4 and has an arc shape in the front and rear direction, a front and rear tilt support 6 slidably engaged along the left surface of the front and rear guide rail 5, and the front and rear A front and rear tilting motor 9 which is mounted on the upper part of the tilting support 6 and can rotate and drive a pinion 8 which meshes with gear teeth 7 formed on the right side of the front and rear guide rails 5, and is mounted on the lower part of the front and rear tilting support 6. In addition, the left and right guide rails 10 that are arcuate toward the left and right
A left and right tilt support 11 which is slidably engaged along the rear surface of the left and right guide rail 10 and has the torch 1 attached to the lower part thereof; and a left and right guide rail 10 which is attached to the lower part of the left and right tilt support 11. A left and right tilting motor 14 capable of rotatively driving a pinion 13 meshing with a gear tooth 12 engraved on the front surface. The front and rear tilting motor 9 rotatably drives the pinion 8 to fix a fixed front and rear guide rail. 5, the front-rear tilt support 6, the left-right guide rails 10, and the left-right tilt supports 11 are tilted in the front-rear direction to set the front retreat angle of the torch 1, and the left-right tilt motor 14 rotationally drives the pinion 13. Left and right tilt support 11 for the left and right guide rails 10
Is tilted in the left-right direction so that the left-right angle of the torch 1 can be set.

Further, as shown in FIGS. 1 to 3, on the left and right side surfaces and the front surface of the torch 1, non-contact type distance measuring sensors 15, 16, 17 capable of measuring the distance to the work 2.
The torch tilt measuring sensor 18 capable of measuring the absolute angle of the torch 1 in the left-right direction and the front-rear direction is provided on the top of the torch 1.

Further, as shown in FIG. 7, the detection signals 19b, 19c, 19d and 19a from the distance measuring sensors 15, 16 and 17 and the torch tilt measuring sensor 18 are inputted to the comparison operation circuit 20. In the comparison calculation circuit 20, the posture information signal 21 is calculated based on the detection signals 19b, 19c, 19d and 19a and output to the welding control device 22. In the welding control device 22, the posture information signal 21 is calculated. Based on the above, the control signal 24 is output to various devices such as the torch holding device 3 and the welding power source 23.

Thus, at the time of welding, the distances Lb, L to the work 2 are measured by the respective distance measuring sensors 15, 16, 17.
c, Ld are measured, and the measured values are detected signals 19b, 1
When the comparison calculation circuit 20 receives the signals 9c and 19d, the comparison calculation circuit 20 detects the detection signals 19b from the distance measuring sensors 15 and 17 on the left and right side surfaces of the torch 1.
The distances Lb and Ld are compared with each other based on 19d to calculate the difference therebetween, and the detection signal 19c from the distance measuring sensor 16 on the front surface of the torch 1 and the distance measuring sensor 1
It is the average value of the distance Lc and the distances Lb and Ld based on the detection signals 19b and 19d from 5, 5 (Lb + L).
d) / 2 is compared, the difference between the two is calculated, and the results of these calculations are taken into the welding control device 22 as the posture information signal 21.

The welding control device 22 controls the left and right tilt motors 14 and 9 of the torch holding device 3 so that the distances Lb, Lc and Ld are all equal based on the posture information signal 21. The signal 24 is calculated and output.

As a result, when the horizontal tilt motor 14 and the front-back tilt motor 9 of the torch holding device 3 are rotationally driven, the distances Lb, Lc, Ld between the distance measuring sensors 15, 16, 17 and the work 2 are equal. Therefore, the lateral angle αi and the frontward receding angle βi of the torch 1 relative to the work 2 are 9 respectively.
It is held at 0 ° (right angle). That is, the torch 1 is tilted in the left-right direction from the x position in FIG. 2 to the x ′ position, and is tilted in the front-rear direction from the y position in FIG. 3 to the y ′ position.

The absolute angle αa on the left and right of the torch 1 and the absolute angle βa on the front and back of the torch 1 measured by the torch tilt measuring sensor 18 on the top of the torch 1 are detected by the comparison calculation circuit 20 as a detection signal 19a and a posture information signal 21. The welding current, the arc voltage, the welding speed, etc. according to the absolute angle of the torch 1 among the welding conditions for each absolute angle of the torch 1 that are taken in by the welding control device 22 and input in advance in the welding control device 22. The optimum welding conditions are automatically selected,
A control signal 24 is output from the welding control device 22 to various devices such as a welding power source 23, and control corresponding to the selected welding condition is performed.

The comparison calculation circuit 20 includes detection signals 19b, 19c, 19d and 19a from the distance measuring sensors 15, 16 and 17 and the torch tilt measuring sensor 18, respectively.
Of course, the posture information signal 21 is constantly fed back to the welding control device 22.

Therefore, according to the above-described embodiment, the welding attitude of the torch 1 is controlled online so that the attitude of the torch 1 with respect to the workpiece 2 is measured every moment, and the absolute position of the torch 1 is controlled. It is possible to control online the optimum welding conditions according to the absolute angle while measuring the angle moment by moment.

The inclination control welding method of the present invention is not limited to the above-mentioned embodiment, and in the above description, the attitude of the torch relative to the work is kept at a right angle. If necessary, the target angle to be controlled may be set to an angle other than a right angle, the distance measuring sensor provided in the torch may be of a contact type, or four distance measuring sensors may be used. May be arranged in a cross shape on the front, rear, left and right of the torch, or three distance measuring sensors may be arranged in the L shape on the left and right sides of the torch and on the front side or the rear side, within the range not departing from the gist of the present invention. It goes without saying that various changes can be made in.

[0023]

According to the inclination control welding method of the present invention described above, various excellent effects as described below can be obtained.

(I) It is possible to control the welding posture and welding condition of the torch with respect to the work piece in an online manner so as to maintain the welding posture optimally.

(II) Due to the above (I), there is no problem that a good welding result cannot be obtained due to the positioning of the torch side at the start of welding, the timing of changing welding conditions changing, etc. It is highly useful for precision welding of thin plates.

(III) Due to the above (I), it becomes possible to use it for various works having different shapes.

[Brief description of drawings]

FIG. 1 is a perspective view showing an embodiment of the present invention.

FIG. 2 is a front view of the torch and the work of FIG.

FIG. 3 is a side view of the torch and the work of FIG.

FIG. 4 is a front view of the torch holding device according to the embodiment of the present invention.

5 is a view in the direction of VV in FIG.

6 is a view in the direction of arrow VI-VI of FIG.

FIG. 7 is a flow sheet showing a control system in one embodiment of the present invention.

[Explanation of symbols]

 1 Torch 2 Work 15 Distance measuring sensor 16 Distance measuring sensor 17 Distance measuring sensor 18 Torch tilt measuring sensor

Claims (1)

[Claims] 1. A distance measuring sensor provided at least at three positions of the torch measures the distance of the torch with respect to the work from moment to moment, and based on the measured values, the right and left angles and the frontward receding angle relative to the work, respectively. While controlling so that the torch can be held at a predetermined angle, the torch tilt measurement sensor provided at the required position of the torch measures the absolute angle of the left and right of the torch and the absolute angle of the front and back moment by moment, and based on the measured value, the torch A tilt control welding method characterized by selecting the optimum welding conditions according to the absolute angle.